This invention relates to a pouch for collecting matter excreted by the body, in particular for collecting excreted liquid. In one aspect, the invention relates to a urine collection pouch, for example, a urostomy pouch or an urine incontinence pouch such as a leg bag. In one form, the pouch is a so-called ventless pouch (i.e. without any dedicated vent for venting gas, such as flatus gas).
Many different designs of urostomy pouch are known. FIG. 1 illustrates schematically an example of a known design of urostomy pouch 10 in common use. The pouch comprises material defining a front wall 11 and rear wall 12 welded together around at least a portion of their common periphery. An entrance aperture 13 is formed in the rear wall 12 towards the upper region of the pouch 10, and a bag-side coupling member 14 is welded around the aperture 13 for releasable fastening to a body-side pad or wafer (not shown) worn on the body.
A urostomy pouch typically does not require any gas vent because the matter entering the pouch is purely liquid (i.e. urine), rather than a mixture of slurry and gas (flatus). Such pouches are therefore xe2x80x9cfilterlessxe2x80x9d and xe2x80x9cventlessxe2x80x9d and do not require the added complexity and expense of a flatus filter and vent, or a liquid/gas separator member.
In use, urine enters the pouch through the aperture 13, and collects in the bottom of the pouch. As more urine is collected, the liquid level in the pouch rises until it approaches the lower edge or point 15 of the entrance aperture 13. The theoretical capacity of the pouch is defined by the level of the edge or point 15; once the liquid exceeds that level, it will tend to overflow back out of the aperture 13 against the wearer""s stoma. In practice, a non-return valve 16 is normally used just below the aperture 13 (for example as described in GB-A-2 145 334). This serves to prevent urine in the pouch from splashing or leaking out through the aperture 13 as the wearer moves about, or sits or lies in a reclined position. The usable capacity of the pouch is then further restricted to the level 16a of the non-return valve 16.
Such a pouch (and also a method of inserting a superabsorbent sheet through the entrance aperture and non return valve) are also described for example in GB-A-2268882.
Reference is also made to U.S. Pat. No. 5,549,587 which describes an ostomy bag with a flatus filter and having a liquid-gas separation device disposed within the bag. The separator is made of an absorbent material to collect liquids and separate these components from any gas entering the bag through the stomal aperture. The separator is spaced from the bag""s filter to further enhance the gas-liquid separation. The separator may be disposed within the bag in an attached or unattached configuration. A perforated wall may be included within the bag to minimize clogging of the separator by solids so as to improve gas-liquid separation. The essence of this patent is to use an absorbent member in a pouch having a gas vent/filter in order to separate the gas and liquid components of the bag contents, and to provide some protection for the filter. However, this teaching is irrelevant for a pouch such as urostomy pouch which does not require a gas filter and vent; the sole motivation for the separator design is to address the problem of liquid-gas separation for the vent (whether or not a filter is provided).
It would be desirable, in one aspect, to increase the usable capacity of the pouch relative to the interior volume of the pouch, especially for a liquid collection pouch.
In contrast to the above prior art design, one aspect of the present invention is to provide, in a pouch comprising first and second walls with an entrance aperture in the first wall, means extending above the lower level of the entrance aperture for collecting liquid in at least a portion of an upper region of the pouch above said lower level of the aperture.
The invention can therefore enable the urine capacity of the pouch to be increased, by making use of the hitherto unavailable upper volume of the pouch (above the lower level of the entrance aperture).
Preferably, the means extending above the lower level of the entrance aperture comprises one or more wicking members capable of drawing liquid upwardly by a wicking effect.
Preferably, the means extending above the lower level of the entrance aperture comprises liquid gelling material. Preferably, the material is a so-called super absorbent material. A suitable super absorbent material is or comprises sodium polyacrylate. In a preferred embodiment, the superabsorbent material is in the form of a laminate, the superabsorbent powder being compressed or bonded between 2 papers, for example tissue paper and/or weldable paper. Such a laminate holds the superabsorbent powder together, enabling it to be handled and cut during manufacture. It also prevents the suderabsorbent from disintegrating inside the pouch in use. This is particularly important if a thin pad is used in the pouch. A further advantage is that, if a weldable paper sheet is used as one of the webs of the laminate, the laminate can be welded to the pouch wall to secure the laminate in position.
Preferably, the super-absorbent laminate material comprises, or is part of a composition which also comprises, glycerol. The glycerol can act as a humectant, to improve the wicking effect in the material, and avoid gel-locking. The composition is preferably as described in GB-A-2301350 or GB-A-2325432.
Preferably, the absorbent material is arranged in the form of one or more pads or other members which retain substantially their integrity when wetted by urine. This can prevent the superabsorbent laminate, or the gel produced when wet, from tending to fall to the bottom of the pouch, which might otherwise reduce the advantage of being able to use the upper region of the pouch as a collection volume. If desired the pad can be attached to a wall of the pouch, for example, by adhesive or welding. This also prevents the pad from tending to drop down in the pouch, and also serves to positively locate the pad during manufacture.
Particularly when the pouch is a urostomy pouch, it is preferred that an intermediate wall be provided between said means (for example an absorbent member), and the entrance aperture. The intermediate wall can serve to screen the aperture from direct communication with said means. Therefore, the wearer""s sensitive stoma can be protected from direct contact with, for example, the superabsorbent laminate material, which can otherwise cause irritation of the stoma from prolonged contact. The intermediate wall may extend part-way down the length of the pouch.
Preferably, a non-return system is employed to allow liquid to pass from the entrance aperture towards the absorbent material, but to obstruct matter passing back towards the entrance aperture. The non-return system may, if desired, comprise material with directional flow characteristics, and/or it may rely on liquid being gellified.
In a second broad aspect, the invention provides a pouch comprising walls defining first and second chambers arranged with a portion of one generally horizontally in front of a portion of the other, an entrance aperture communicating with the first chamber, and wherein, in use, liquid entering the pouch through the entrance aperture flows into the first chamber and from the first chamber directly or indirectly into the second chamber, the first chamber acting as an intermediate chamber for the liquid, and the second chamber acting as a collection chamber.
Preferably, the pouch comprises an entrance aperture in a face thereof.
Preferably, the first and second chambers are separated by one or more walls acting as a non-return system to allow liquid in the first chamber to enter the second chamber, but to obstruct matter in the second chamber from passing into the first chamber.
Preferably, the non-return system is effective to prevent liquid in the second chamber from passing back to the first chamber.
Preferably, the one or more walls are made of material which is liquid permeable in one direction, but which obstructs the passage of liquid in the opposite direction. Such material may, for example, include directional pores.
Preferably, the second chamber contains material for gellifying liquid in the second chamber. Preferably the material is an absorbent, such as a super-absorbent.
Preferably, the pouch is a urostomy pouch or an incontinence pouch.
In a third broad aspect, the invention provides a pouch for collecting matter excreted by the body, the pouch having an outer profile consisting substantially of a first upper curved arcuate portion and a second lower arcuate portion, at least one of the arcuate portions having a maximum transverse dimension greater than the transverse dimension at the point where the first and second portions meet.
Such a pouch profile thus defines a form of figure-of-eight shape. The transverse dimensions of the upper and lower portions may be similar, or one of the portions (for example, the lower portion) may have a greater transverse dimension than the other portion.
Such a pouch profile can assist in controlling the extent to which the pouch, in use, will tend to bulge outwardly as the pouch fills. In the prior art, such control has hitherto only been possible by incorporating one or more spot welds to define a quilted arrangement. However, such spot welds result in high stresses in the pouch material surrounding the weld, and in the weld itself; such spot welds have, sometimes, been known to fail.
The region in which one arcuate region joins the other can also act as a form of marker or indicator, to indicate to the user in a highly unambiguous manner, when the pouch is nearly full and will soon require replacement or emptying.
Preferably, the profile has a waist region at the point where the upper and lower arcuate portions meet. Depending on the design of the pouch, the waist may be used to form a non-return valve within the pouch, by virtue of two closely spaced sheets constricted which allow liquid to dribble therebetween, but which tend to prevent splashing back of the liquid.
Preferably, at least one of the upper and lower portions corresponds to an arc of a circle.
Preferably, the pouch comprises an entrance aperture having a centre located generally in register with a centre of curvature of the upper portion.
Preferably, the pouch carries a coupling member welded to the pouch wall in register with the aperture.
In a fourth aspect, the invention provides a pouch for collecting matter excreted by the body, the pouch having a welded seam, the seam defining an interior pouch profile consisting substantially of a first upper curved arcuate portion and a second lower arcuate portion, at least one of the arcuate portions having a maximum transverse dimension greater than the transverse dimension at the point where the first and second portions meet.
In a yet further aspect, the invention provides a pouch consisting generally of material defining a front wall and a rear wall, at least one of the walls having an entrance aperture for allowing material to enter the pouch for collection therein. The pouch may be intended to be disposable when full, or it may be drainable.
In a yet further aspect, the invention provides a urine collection pouch, the pouch comprising first and second walls, an entrance aperture in the first wall for allowing urine into the pouch, and the pouch defining first and second interior chambers, the first chamber being in communication with the aperture, and the second chamber containing an absorbent material.
Preferably, the first chamber acts as an intermediate chamber from which urine flows to the second chamber to interact with the absorbent material.
Preferably, the absorbent material turns the urine liquid to a gel. Preferably, the material is a superabsorbent material.
Preferably, the entrance aperture is in a face of the pouch.
Preferably, the pouch is a urostomy pouch or a urine incontinence pouch.
The above aspects of the invention may either be used independently, or two or more aspects may be used in combination to achieve yet further advantages.